The longer a roof lasts—and the more resilient it is in standing up to weather, fire, and other environmental conditions—the longer it stays out of landfills and the less likely it will need to be replaced with new materials. This durability and longevity of PVC roofing material contribute greatly to its reputation as a green building material choice.
Many building envelope systems will be replaced several times throughout the baseline RSL of 75 years for long-life buildings. The RSL of such systems and products is often the largest driver of their embodied carbon impact over the life of the building. For example, if product A has an RSL of 15 years and product B has an RSL of 25 years, the products will be replaced four and two times, respectively, after the original installation.
Even if product A’s embodied carbon is 10 percent less than product B’s, during the building’s RSL, product A’s total embodied carbon impact will be 50 percent greater than product B’s because product A needs to be replaced more often. Even with a 15 percent differential, product A’s total impact will be 41 percent greater than product B’s over the building’s RSL.
This example demonstrates why it is vital to consider multiple performance attributes for material selection. Since reliance on a cradle-to-gate method for embodied carbon may lead to unintended consequences, considering more than one metric in assessing a material’s carbon impact, such as its RSL and replacement cycles, provides a truer estimate of the product’s impacts over the life of a building.
Author
Bill Bellico is the vice-president, marketing and inside sales, at Sika USA. Bellico has worked in the commercial construction industry for 20 years in Sika’s roofing and flooring divisions. He began his career in sales and evolved into roles in sales and marketing management, as well as leading digital transformation projects for the company. He is a LEED-accredited professional with a strong background in sustainability. Bellico is the current acting marketing chair for the Chemical Fabrics & Film Association (CFFA)—vinyl roofing division, as well as the Vinyl Sustainability Council, and is also a participating member of the Roofing Technology Think Tank (RT3). He has bachelor’s degrees in English and psychology from the Bridgewater State University and completed the business strategy certificate program from Cornell University.
